Table 1.

Keratometric, pachymetric, and pachymetric progression indices of study groups

Parameter	Keratoconus eyes, mean (SD) (n=22)	Normal eyes, mean (SD) (n=48)	P-value (Mann–Whitney U)	Mean difference (95% CI)
Central keratometry fat axis, D	42.99 (2.2)	42.6 (1.3)	0.658	0.35 (−0.49, 1.19)
Central keratometry steep axis, D	44.6 (2.7)	44.0 (1.3)	0.455	0.54 (−0.42, 1.49)
Mean central keratometry, D	43.7 (2.1)	43.3 (1.3)	0.29	0.40 (−0.41, 1.22)
Central astigmatism, D	2.25 (1.9)	1.4 (0.7)	0.173	0.84 (0.22, 1.5)
Cornea minimum radius of curvature, mm	7.09 (0.59)	7.39 (1.1)	0.001	−0.3 (−0.78, 1.75)
Pachymetry apex, μm	532.3 (38.9)	533.4 (28.2)	0.766	−1.2 (−17.6, 15.2)
Pachymetry thinnest location, μm	518.8 (39.9)	528.85 (27.85)	0.475	−10.04 (−26.5, 6.4)
Pachymetry pupil center, μm	535.9 (39.87)	534.1 (28.02)	0.578	1.81 (−14.7, 18.3)
Thinnest location distance from apex in X axis, mm	0.46 (0.3)	0.42 (0.23)	0.800	0.04 (−0.09, 0.17)
Thinnest location distance from apex in Y axis, mm	0.87 (0.35)	0.53 (0.26)	<0.001	0.34 (0.19, 0.49)
Thinnest location absolute distance from apex, mm	1.01 (0.38)	0.73 (0.19)	0.001	0.28 (0.15, 0.42)
Pachymetric progression index, min	0.94 (0.33)	0.58 (0.14)	<0.001	0.36 (0.25, 0.48)
Pachymetric progression index, avg	1.47 (0.47)	0.94 (0.15)	<0.001	0.52 (0.38, 0.67)
Pachymetric progression index, max	2.15 (0.86)	1.31 (0.22)	<0.001	0.837 (0.57, 1.1)
Ambrósio relational index, avg	390.6 (134.5)	576.0 (111.7)	<0.001	−185.4 (−246.7, −124.2)
Ambrósio relational index, max	279.3 (106.9)	418.9 (97.2)	<0.001	−139.7 (−191.2, 88.2)

Abbreviations: avg, average; CI, confidence interval; max, maximum; min, minimum; SD, standard deviation; n, number of eyes.